1. Field of the Invention
The present invention relates to grilles for air conditioning provided in automobiles and others.
2. Description of the Related Art
The following grille for air conditioning provided mainly on the instrument panel of an automobile is publicly known, which is disclosed in the Japanese Utility Model Laid-open No. 51-2849. Namely, the wind direction adjusting plates made of leaf springs are fitted in a case being deformed in a shape of an arc. Said wind direction adjusting plates are given pressure by an operation lever, thereby the direction of an arc is changed to the right or the left, enabling the direction of the wind to be changed.
As an example of this type of the wind direction adjusting plate, there is disclosed in the Japanese Utility Model Laid-open No. 51-6643 a wind direction adjusting plate with V-shaped slits formed at equal intervals as shown in FIG. 13 on the upper and the lower surfaces to make easily curved.
In the above described type of the grille for air conditioning, however, a considerable amount of operation force was needed to change the direction of the wind by curving the wind direction adjusting plate by means of the operation lever because of the position of the operation lever and the resiliency of the wind direction adjusting plate. Moreover, when the wind direction adjusting plate was curved, the plate was apt to be disadvantageously twisted or distorted because of its free curvability.
Also, there was a problem that the strength and the rigidity of each member of the grille must be reinforced or the precision of bearings be enhanced in order to solve the above problems, resulting in the increasing weight and cost of the whole of the grille for air conditioning.
Also, there was a problem in the conventional type of the grille for air conditioning that the structure was complicated and nevertheless, the arc of the wind direction adjusting plate was not smooth. Moreover, the end portion of the wind direction adjusting plate at the wind leading-in side is not aligned in the same direction as the wind led in, resulting in occurrence of a noise when sending especially a strong wind.
There was a problem that since the force from the operation lever to change the direction of the wind is not transmitted uniformly to the whole of the wind direction adjusting plate, the wind direction adjusting plate is twisted, thereby the flow of the wind is disordered and swirled, resulting in occurrence of a noise and the unfavorable direction of the wind. The above-described wind direction adjusting plate 21 shaped as shown in FIG. 13 had a problem that the flow of the wind was disordered owing to the concavities and the convexities of the slits 22, resulting in occurrence of a noise and the unfavorable direction of the wind.
Also, there was a problem that since the force from the operation lever to change the direction of the wind was not transmitted uniformly to the whole of the wind direction adjusting plate, the plate was twisted, the flow of the wind was disordered and swirled, resulting in occurrence of a noise and unfavorable direction of the wind, as described in the above.
Further, in order to change the direction of the wind, the operation force to cause resilient deformation to the wind direction adjustment plate is needed in addition to the frictional force of the bearings and others of the wind direction adjusting plate. Accordingly, there was a problem that the operation force became heavy in cooperation with the increasing degree of the curvature of the wind direction adjusting plate.
Further, there was a problem that when the wind direction adjusting plate was largely curved by the operation lever, the curved state of the wind direction adjusting plate was restored to the original state due to a small frictional force of the bearings and others of the wind direction adjusting plate.